Let's bring in our chief white house correspondent jake tapper who's in for george stephanopoulos on "this week" today. In the eight days since paul ryan was selected as romney's running mate, medicare is his achilles heel, by bringing out his mom, has he turned that dynamic around? Not right. It was a nice florida rally. The dynamic hasn't been turned around. Many house republicans and republican officials are very nervous about medicare being the topic as opposed to jobs and the economied and 8.3 unemployment. There's a very aggressive pushback by the romney/ryan teams. Talking about cuts the president made to medicare to pay for obama care and other benefits in that program and also, of course, bringing out his mother, talking about the need to have a serious discussion to preserve medicare for future retirees. That's their aggressive approach. All of this back and forth, is super confusing who's worried about their future in the medicare. Let's talk about this new attack ad that team obama has launched. I want to play for it and get your response on the back end. Check it out. Both romney and ryan back proposals to outlaw abortion. For women the choice is ours. How potent is this for team obama? They think very potent. As we talked about before, women voters are the key in this election. President obama needs to win them overwhelming and they think that this position from romney and ryan, on the issue of abortion and other issues related to birth control, can help them with women in northern virginia the suburbs of philadelphia. Shaker heights, ohio, et cetera. Women who may be am by va lent of president obama, maybe a little bit more worried about romney/ryan. They're trying to plant those seeds of doubt and make romney/ryan even more unacceptable. Jake has a big show this morning.

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